Sewing-machine



G. S. HILL.

SEWING MACHINE. APPLICATION FILED MAY n, 1911.

Patented Aug- 30, 1921.

UNITED STATES PATENT QFFICELHT GEORGE s. HILL, or, STRAIFORD, NEW HAMPSHIRE, ASSIGNOR, .BY MESNE ASSIGLL MENTS, TO UNITED SHOE MACHINERY SEY, A. CORPORATION OF NEW JERSEY.

CORlORATION, OF PATERSON, NEKV JER- SEWING-MACHINE.

Specification of Letters Patent. Patented Aug,

Original application filed June 19, 1916,,Seria1 No. 104,449; Divided and this application filed May 11, A 1917. Serial no. 167,933. I

To all whom it may concern:

Be it known that I,"GEORGE S. -HILL, a citizen of the United States, residing at Straiford,-in the county of Strafi'ord and State of-New Hampshire, have invented certain newand useful Improvementsin Sewing-Machines; and I do hereby declare the following to be a full clear, andexactfldescription of the invention,'such as will enable others skilled in the art to which it appertains to make and use the same.

The invention relates to thread controlling mechanism for sewing machines.

The present application is a division of application Serial No. 104,449, filed June19,

The object" of the inventionis to provide novel and improved-devices for controlling the'needle threadbetween the needle bar and the thread supply which are simple in con struotion andefficient in operation, and which are well adapted for cooperating with aneedle mechanism driven at high speed."

To these ends the invention comprises the features of construction and combinatlons of parts hereinafter described and referred to inthe claims. 7 v p The invention will be readily understood from. an inspection of the accompanying drawings and the following detailed description of the mechanism illustrated therein.

In the drawings, Figure 1 is a front elevation, partly in section, showing so much of a buttonhole sewing machine as is necessary to illustrate the application of the present improvement thereto, and Fig. 2 is a detail side elevation showing the thread controlling devices, the tension device being removed to show the'parts behind it.

In the-drawings the invention is shown as embodied in a buttonhole making-ma'- chine comprisingv in general a'cutter which operatesto out the buttonhole slit after the completion of the sewing,- a reciprocating and laterally moving work clamp, and a sewing mechanism which is rotated during the sewing about the eye of the buttonhole, and which comprises a" vertically reciprocating and laterally vibrating upper needle and cooperating looping and loop spreading devices. arranged belowthe work; e

In the machine shown the Work clamps, indicated at 2, are mounted upon the work supporting plates 4 which are pivoted on a longitudinally and laterally moving clamp" carriage 6. The clampsare automatically closed at the beginning of the sewing, and are automatically opened after the completion of the buttonhole, "by mechanism which forms no part of-the present invention, and which need not be described. The buttonholeslit is cut at the completion of the sew-e ing by a cutter-indicated at 8 which is operated by a camon the main cam shaft of the machine, The work is carried bythe clamp over a'thro'at plate 10: mounted on a turret 12 whichcarries the under looping and -loop op'e'rate with the needle informing the Well known Humphrey stitch. The needle 16 is eccentrically mounted in a hollow needlebar 1S wliich rec'i'procates in acarrier sleeve20. The carrier sleeveis reciprocated through a bell crank tal arm of'which is connected "by aball joint lever indicatedat 22, the horizon with the upper end of the sleeve and the ver-' 2 tical arm of which is indicated at 24. The lower end of the sleeve is moved laterally during its reciprocation bya'linkfifi, one

end of which is connected to the sleeve, and the other end of which is connected with a pivot 28 on the rotaryhead 30. As thesleeve lower end of the sleeve and the needle bar toward the right,'so that the needle bar will be in position for the depth stitch, and as the sleeve rises the link acts to swing the sleeve,

rierwill be moved to the right during one:

moves downward, the link acts to swing the reciprocation of'the needle,andto the left during the "succeeding" reciprocation, and

thus thegneedle will be vibrated" to *alternately form "depth and edge 01 slit stitches.

The needle bar, is reciprocated by a crank 32 which is carried by a shaft 34 and is connected to the needle bar by a link 36. The rotary head 30 in which the CilIIlGI' SlGGVB and needle bar are carried, and the rotary turret 12 in which the looper mechanism is passes la erally under a thread guiding finger 46 to a tension device d8, from which it leads through suitable guides to the thread supply. The thread guiding finger 4&6 and the tension device 48 are arranged at one side of the needle bar, and the finger is so mounted that it may be adjusted vertically to vary; the take up action of the needle bar as it is re tracted. In order to retain or hold the thread substantially taut during the downwardstroke of the needle, and until the needle eye enters the work, a thread retainer 50 is arranged adjacent to the upper end of the needle bar when the bar is in retracted position, and is constructed to retain the thread until the thread is withdrawn therefrom by the downward stroke of the needle after its eye has entered the work and the needle is acting to carry a loop below thework. As shown, this thread retainer comprises a spring clip secured to the cap plate 52 which is removably attached to the head of the machine in front of the upper needle mechanism. 7

During the final upward movement of the needle bar the thread leading from the upper end of the needle bar to the guiding finger 46, or to the tension device, passes between I the members of the clip, as indicated in the drawings. During the first part of the downward stroke of the needle bar, the thread retainer frictionally holds the thread so that the needle slides down the standing thread until its eye enters the work. This insures the proper control of the thread and holds it substantially taut between the preceding stitch and the tension device until slack thread is required for the formation ofthe needle loopbelow the work. As the eye of the needle enters the work, carrying aloop of thread with it, the pull on the thread withdraws it from the thread retainer, so that slack thread is provided between the upper end of the needle bar and the tension device for the loop carried below the work by the needle. During the upward stroke of the needle bartheupper end of the needle bar acts as a takeup to set the stitch, and thereafter draws thread through the tension device forthe succeeding stitch. The

takeup action of the needle bar may be varied by vertical adjustment of the thread guiding finger 46, so that it will deflect the thread between the tension device and theupper end of the needle bar to a greater or less extent.

While it is preferred to employ the specific construction and arrangement of parts shown and described in embodying the invention in a machine of the type shown, it will be understood that this construction and arrangement are not essential to the broader scope of the invention, but may be varied or modified as found desirable or best suit ed to the construction of the machine in which it is to be embodied.

Having explained the nature and object of the invention, and specifically described one form of mechanism in which itmay be embodied, what is claimed is 1. A sewing machine having, in combination, a vertically reciprocating'upper needle bar, complemental under mechanism comprising looper and loop spreader points cooperating with the needle to form overseam stitches, a'thread guide on the upper part of the needle bar, a thread guide at one side of the needle bar against which the thread is drawn by the needle bar during the latter part only of the upward stroke of'the' bar, and astationary thread retainer arranged between the guides and constructed to frictionally hold the "thread until withdrawn therefrom by the action of the needle eye on the thread, as the eye carries a loop of thread through the work.

2. Asewing'machine'having, in combination, a vertically reciprocating and hollow needle bar through which the upperthread passes, a thread guide at one sideof the,

path of travel of the upper end of thebar against which the thread is drawn by the latter part only of the upward stroke of the bar, and a thread retaining'clip between the guide and the upper end of the bar into which the thread is carried by the final upward movement of the needle bar and from which itis drawn by the action of the needle eye on the thread as the eye carries a loop of thread through the work. i

3. A sewing machine, having, in combina-' tion,a vertically reciprocating hollow-needle bar through which the upper thread passes,

compleinental under mechanism cooperating therewith to form overseam stitches, a tension'devicearranged at one side of the needle bar, a vertically adjustable .thread guide under which the threadpasses from the tension device to theupper end of the needle bar,and a thread retainer between the guide and end of the bar for retaining the thread until the needle enters the work.

- GrEORGrE S. HILL." 

